Box plots are used to summarize data graphically. To construct a box plot, first find the minimum data value, the lower quartile, the median, the upper quartile, and the maximum data value. These five statistics are then marked on a number line with a box drawn from the lower quartile to the upper quartile. The median is marked inside the box.

This material is based upon work supported by the
National Science Foundation under Grant DUE-0226284.
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